Contrast media reactions and extravasation: Relationship to intravenous injection rates

PURPOSE: To evaluate the belief that the frequencies of contrast material extravasation and minor, nonidiosyncratic contrast material reactions correlate with intravenous injection rates. MATERIALS AND METHODS: Complications of 6,660 consecutive injections of contrast material for computed tomography were prospectively recorded. Ionic (n = 4,851) or nonionic (n = 1,809) contrast material was injected at 0.5-4.0 mL/sec. The injection rate was 1.9 mL/sec or less in group 1 (n = 2,899), 2.0-2.9 mL/sec in group 2 (n = 2,475) and 3.0-4.0 mL/sec in group 3 (n = 1,286). RESULTS: The extravasation rate (0.6%) did not differ significantly between the groups. The reaction rate (8.4%) also did not differ significantly between the groups. The rate of minor reactions (8.0%) was higher with ionic (9.9%) than nonionic (2.9%) contrast material (relative risk = 3.4). The rate of major reactions (0.4%) did not vary significantly with type of contrast material. The rate of nausea or vomiting (3.8%) did not differ significantly between the groups but was higher with ionic (4.9%) than nonionic (1.1%) contrast material (relative risk = 4.5). The rate of severe warmth (2.1%) was significantly higher in group 3 (2.8%) than group 1 (2.0%) or 2 (1.8%). CONCLUSION: No correlations exist between injection rate and extravasation rate or overall reaction rate.